[T] Add back CMakes Test target to make all.

CMakeLists.txt

@@ -153,7 +153,7 @@ IF( OGS_BUILD_TESTS AND NOT IS_SUBPROJECT )
 	IF(CMAKE_VERSION VERSION_LESS 2.8.11)
 		MESSAGE(FATAL_ERROR "CMAKE 2.8.11 or higher is required to build the tests!")
 	ENDIF()
-	ADD_SUBDIRECTORY( Tests EXCLUDE_FROM_ALL )
+	ADD_SUBDIRECTORY( Tests )
 	ADD_SUBDIRECTORY( SimpleTests/MatrixTests EXCLUDE_FROM_ALL )
 	ADD_SUBDIRECTORY( SimpleTests/MeshTests EXCLUDE_FROM_ALL )
 	IF(NOT MSVC AND BLAS_FOUND AND LAPACK_FOUND)